The PDP–11 supports hardware interrupts at four priority levels. Interrupts are serviced by software service routines, which could specify whether they themselves could be interrupted (achieving interrupt nesting).

citation

Wikipedia contributors. (2025, January 14). PDP-11. In Wikipedia, The Free Encyclopedia. Retrieved 17:59, February 28, 2025, from https://en.wikipedia.org/w/index.php?title=PDP-11&oldid=1269362335

Archean (Wikipedia) The Archean Eon (IPA: /ɑːrˈkiːən/ ar-KEE-ən, also spelled Archaean or Archæan), in older sources sometimes called the Archaeozoic, is the second of the four geologic eons of Earth’s history, preceded by the Hadean Eon and followed by the Proterozoic. The Archean represents the time period from 4,031 to 2,500 Ma (millions of years ago). The Late Heavy Bombardment is hypothesized to overlap with the beginning of the Archean. The Huronian glaciation occurred at the end of the eon.

PDP-11 (Wikipedia) The PDP–11 is a series of 16-bit minicomputers originally sold by Digital Equipment Corporation (DEC) from 1970 into the late 1990s, one of a set of products in the Programmed Data Processor (PDP) series. In total, around 600,000 PDP-11s of all models were sold, making it one of DEC’s most successful product lines. The PDP-11 is considered by some experts to be the most popular minicomputer.